#include <iostream>
#include <unistd.h>
#include <signal.h>

void hander(int sig)
{
    std::cout << "get a sig: " << sig << std::endl;
}

int main()
{
    signal(2, hander);
    while (true)
    {
        std::cout << "hello bit, pid: " << getpid() << std::endl;
        sleep(1);
    }
}